1. Field of the Invention
The present invention relates to eyeglasses and more particularly to an improved auxiliary frame releasably mounted on the frame of a pair of sunglasses or the like.
2. Description of Related Art
Conventionally, a wearer of sunglasses likes to mount an auxiliary frame on the frame of the sunglasses. The auxiliary frame typically has a pad on the back for providing a degree of comfort to the wearer and/or protection. A conventional such auxiliary frame 30 is shown in FIGS. 1 and 2. As illustrated, a pair of lenses 101 are supported in a frame 10 of a pair of sunglasses 40. The frame 10 further comprises, at its back, two holes 103 at both sides of bridge 102 and two substantially parallelepiped slots 104 each at an endpiece coupled to a pivotable temple 20. Correspondingly, the auxiliary frame 30 comprises two forward tabs 301 at both sides of bridge, two substantially parallelepiped projections 302 each at an endpiece, and a pad at its back. Each of the frame 10 and the auxiliary frame 30 is formed of thermoplastic material so as to be bendable. The auxiliary frame 30 is mounted on the frame 10 with the projections 302 snugly fitted in the slots 104 and the tabs 301 snugly fitted in the holes 103 respectively (see circles D and E of FIG. 2).
Advantageously, the auxiliary frame 30 can be removed from the frame 10 for storage in an unused state. Also, such assembly is adapted to fit different individuals with various head sizes. For example, as shown in FIG. 3, in a case of the wearer having a larger head, the frame 10 flexibly, laterally expands in response thereto. Unfortunately, this may result in a partial or even complete withdrawal of the projections 302 from the slots 104 due to the substantially parallelogramic shapes of the projections 302 and the slots 104 and in turn the forming of a gap 50 at either endpiece between the frame 10 and the auxiliary frame 30 (see circle F). Such gaps 50 will inevitably loosen the whole eyeglasses 40. Thus, the need for improvement still exists.
It is an object of the present invention to provide a flexible, auxiliary frame mounted on a flexible frame of a pair of eyeglasses, the frame including, at its back, a hole in a center of a bridge, two protrusions having a larger bottom at both sides of the hole, and two slots at endpieces, the auxiliary frame comprising a forward tab at a bridge thereof; two grooves at both sides of the tab; two projections having a larger outer end disposed at endpieces thereof; and a rear pad, wherein the projections are matingly fitted in the slots, the tab is fitted in the hole, and the protrusions are fitted in the grooves respectively, and the frame together with the auxiliary frame are adapted to flexibly expand in response to a lateral bending.
In one aspect of the present invention each of the frame and the auxiliary frame is formed of thermoplastic material.
The above and other objects, features and advantages of the present invention will become apparent from the following detailed description taken with the accompanying drawings.